1. Field
The present invention relates to a rupture disk capable of minimizing damage to a system by allowing insulated gas to be discharged in advance at the time of an increase in an internal pressure, and a gas insulated switchgear having the same.
2. Description of the Related Art
In a gas insulated switchgear (GIS), which is one of the circuit breakers in various electric circuits. GIS is filled by gas as an insulator in the circuit breaker. A sulphur hexafluoride (SF6) gas that has been spotlighted as an insulated gas has an insulation effect three times higher than that of air. This insulation effect increases when a pressure is applied to the sulphur hexafluoride (SF6) gas. Due to these electrical characteristics of the SF6 gas, the circuit breaker may obtain a good insulation performance even in a space smaller than that of an existing case, it has been mainly used in the gas insulated switchgear accordingly.
When the gas insulated switchgear in which the SF6 gas is filled is maintained under a predetermined pressure, a problem does not occur. However, in the gas insulated switchgear in which the SF6 gas is filled, when a short circuit occurs due to an electrical accident, energy suddenly increases to raise a temperature, an internal pressure suddenly increases accordingly and a pressure container explodes. In this case, a recovery time increases, which may cause economical loss to astronomically increase and damage to the environment and human life. Therefore, it is important to prevent explosion of an apparatus in advance.
In order to solve the sudden increase in the pressure in the gas insulated switchgear, a spring type safety valve has been suggested. However, in the spring type safety valve, it is often difficult to solve an unexpected sudden increase in an accidental pressure rise. Further, in order to solve this problem, a scheme of using a rupture disk has also been suggested. However, in this scheme, there is a disadvantage in that fragments are blocked, such that a pressure does not smoothly decrease or a human is injured by the fragments.